// Copyright 2014 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// Author: Skal (pascal.massimino@gmail.com)

#include <assert.h>
#include <stddef.h>
#include <stdlib.h>

#include "src/dsp/cpu.h"
#include "src/dsp/dsp.h"
#include "src/enc/cost_enc.h"
#include "src/enc/vp8i_enc.h"
#include "src/webp/types.h"

//------------------------------------------------------------------------------
// Boolean-cost cost table

const uint16_t VP8EntropyCost[256] = {
    1792, 1792, 1792, 1536, 1536, 1408, 1366, 1280, 1280, 1216, 1178, 1152,
    1110, 1076, 1061, 1024, 1024, 992,  968,  951,  939,  911,  896,  878,
    871,  854,  838,  820,  811,  794,  786,  768,  768,  752,  740,  732,
    720,  709,  704,  690,  683,  672,  666,  655,  647,  640,  631,  622,
    615,  607,  598,  592,  586,  576,  572,  564,  559,  555,  547,  541,
    534,  528,  522,  512,  512,  504,  500,  494,  488,  483,  477,  473,
    467,  461,  458,  452,  448,  443,  438,  434,  427,  424,  419,  415,
    410,  406,  403,  399,  394,  390,  384,  384,  377,  374,  370,  366,
    362,  359,  355,  351,  347,  342,  342,  336,  333,  330,  326,  323,
    320,  316,  312,  308,  305,  302,  299,  296,  293,  288,  287,  283,
    280,  277,  274,  272,  268,  266,  262,  256,  256,  256,  251,  248,
    245,  242,  240,  237,  234,  232,  228,  226,  223,  221,  218,  216,
    214,  211,  208,  205,  203,  201,  198,  196,  192,  191,  188,  187,
    183,  181,  179,  176,  175,  171,  171,  168,  165,  163,  160,  159,
    156,  154,  152,  150,  148,  146,  144,  142,  139,  138,  135,  133,
    131,  128,  128,  125,  123,  121,  119,  117,  115,  113,  111,  110,
    107,  105,  103,  102,  100,  98,   96,   94,   92,   91,   89,   86,
    86,   83,   82,   80,   77,   76,   74,   73,   71,   69,   67,   66,
    64,   63,   61,   59,   57,   55,   54,   52,   51,   49,   47,   46,
    44,   43,   41,   40,   38,   36,   35,   33,   32,   30,   29,   27,
    25,   24,   22,   21,   19,   18,   16,   15,   13,   12,   10,   9,
    7,    6,    4,    3};

//------------------------------------------------------------------------------
// Level cost tables

// fixed costs for coding levels, deduce from the coding tree.
// This is only the part that doesn't depend on the probability state.
const uint16_t VP8LevelFixedCosts[MAX_LEVEL + 1] = {
    0,    256,  256,  256,  256,  432,  618,  630,  731,  640,  640,  828,
    901,  948,  1021, 1101, 1174, 1221, 1294, 1042, 1085, 1115, 1158, 1202,
    1245, 1275, 1318, 1337, 1380, 1410, 1453, 1497, 1540, 1570, 1613, 1280,
    1295, 1317, 1332, 1358, 1373, 1395, 1410, 1454, 1469, 1491, 1506, 1532,
    1547, 1569, 1584, 1601, 1616, 1638, 1653, 1679, 1694, 1716, 1731, 1775,
    1790, 1812, 1827, 1853, 1868, 1890, 1905, 1727, 1733, 1742, 1748, 1759,
    1765, 1774, 1780, 1800, 1806, 1815, 1821, 1832, 1838, 1847, 1853, 1878,
    1884, 1893, 1899, 1910, 1916, 1925, 1931, 1951, 1957, 1966, 1972, 1983,
    1989, 1998, 2004, 2027, 2033, 2042, 2048, 2059, 2065, 2074, 2080, 2100,
    2106, 2115, 2121, 2132, 2138, 2147, 2153, 2178, 2184, 2193, 2199, 2210,
    2216, 2225, 2231, 2251, 2257, 2266, 2272, 2283, 2289, 2298, 2304, 2168,
    2174, 2183, 2189, 2200, 2206, 2215, 2221, 2241, 2247, 2256, 2262, 2273,
    2279, 2288, 2294, 2319, 2325, 2334, 2340, 2351, 2357, 2366, 2372, 2392,
    2398, 2407, 2413, 2424, 2430, 2439, 2445, 2468, 2474, 2483, 2489, 2500,
    2506, 2515, 2521, 2541, 2547, 2556, 2562, 2573, 2579, 2588, 2594, 2619,
    2625, 2634, 2640, 2651, 2657, 2666, 2672, 2692, 2698, 2707, 2713, 2724,
    2730, 2739, 2745, 2540, 2546, 2555, 2561, 2572, 2578, 2587, 2593, 2613,
    2619, 2628, 2634, 2645, 2651, 2660, 2666, 2691, 2697, 2706, 2712, 2723,
    2729, 2738, 2744, 2764, 2770, 2779, 2785, 2796, 2802, 2811, 2817, 2840,
    2846, 2855, 2861, 2872, 2878, 2887, 2893, 2913, 2919, 2928, 2934, 2945,
    2951, 2960, 2966, 2991, 2997, 3006, 3012, 3023, 3029, 3038, 3044, 3064,
    3070, 3079, 3085, 3096, 3102, 3111, 3117, 2981, 2987, 2996, 3002, 3013,
    3019, 3028, 3034, 3054, 3060, 3069, 3075, 3086, 3092, 3101, 3107, 3132,
    3138, 3147, 3153, 3164, 3170, 3179, 3185, 3205, 3211, 3220, 3226, 3237,
    3243, 3252, 3258, 3281, 3287, 3296, 3302, 3313, 3319, 3328, 3334, 3354,
    3360, 3369, 3375, 3386, 3392, 3401, 3407, 3432, 3438, 3447, 3453, 3464,
    3470, 3479, 3485, 3505, 3511, 3520, 3526, 3537, 3543, 3552, 3558, 2816,
    2822, 2831, 2837, 2848, 2854, 2863, 2869, 2889, 2895, 2904, 2910, 2921,
    2927, 2936, 2942, 2967, 2973, 2982, 2988, 2999, 3005, 3014, 3020, 3040,
    3046, 3055, 3061, 3072, 3078, 3087, 3093, 3116, 3122, 3131, 3137, 3148,
    3154, 3163, 3169, 3189, 3195, 3204, 3210, 3221, 3227, 3236, 3242, 3267,
    3273, 3282, 3288, 3299, 3305, 3314, 3320, 3340, 3346, 3355, 3361, 3372,
    3378, 3387, 3393, 3257, 3263, 3272, 3278, 3289, 3295, 3304, 3310, 3330,
    3336, 3345, 3351, 3362, 3368, 3377, 3383, 3408, 3414, 3423, 3429, 3440,
    3446, 3455, 3461, 3481, 3487, 3496, 3502, 3513, 3519, 3528, 3534, 3557,
    3563, 3572, 3578, 3589, 3595, 3604, 3610, 3630, 3636, 3645, 3651, 3662,
    3668, 3677, 3683, 3708, 3714, 3723, 3729, 3740, 3746, 3755, 3761, 3781,
    3787, 3796, 3802, 3813, 3819, 3828, 3834, 3629, 3635, 3644, 3650, 3661,
    3667, 3676, 3682, 3702, 3708, 3717, 3723, 3734, 3740, 3749, 3755, 3780,
    3786, 3795, 3801, 3812, 3818, 3827, 3833, 3853, 3859, 3868, 3874, 3885,
    3891, 3900, 3906, 3929, 3935, 3944, 3950, 3961, 3967, 3976, 3982, 4002,
    4008, 4017, 4023, 4034, 4040, 4049, 4055, 4080, 4086, 4095, 4101, 4112,
    4118, 4127, 4133, 4153, 4159, 4168, 4174, 4185, 4191, 4200, 4206, 4070,
    4076, 4085, 4091, 4102, 4108, 4117, 4123, 4143, 4149, 4158, 4164, 4175,
    4181, 4190, 4196, 4221, 4227, 4236, 4242, 4253, 4259, 4268, 4274, 4294,
    4300, 4309, 4315, 4326, 4332, 4341, 4347, 4370, 4376, 4385, 4391, 4402,
    4408, 4417, 4423, 4443, 4449, 4458, 4464, 4475, 4481, 4490, 4496, 4521,
    4527, 4536, 4542, 4553, 4559, 4568, 4574, 4594, 4600, 4609, 4615, 4626,
    4632, 4641, 4647, 3515, 3521, 3530, 3536, 3547, 3553, 3562, 3568, 3588,
    3594, 3603, 3609, 3620, 3626, 3635, 3641, 3666, 3672, 3681, 3687, 3698,
    3704, 3713, 3719, 3739, 3745, 3754, 3760, 3771, 3777, 3786, 3792, 3815,
    3821, 3830, 3836, 3847, 3853, 3862, 3868, 3888, 3894, 3903, 3909, 3920,
    3926, 3935, 3941, 3966, 3972, 3981, 3987, 3998, 4004, 4013, 4019, 4039,
    4045, 4054, 4060, 4071, 4077, 4086, 4092, 3956, 3962, 3971, 3977, 3988,
    3994, 4003, 4009, 4029, 4035, 4044, 4050, 4061, 4067, 4076, 4082, 4107,
    4113, 4122, 4128, 4139, 4145, 4154, 4160, 4180, 4186, 4195, 4201, 4212,
    4218, 4227, 4233, 4256, 4262, 4271, 4277, 4288, 4294, 4303, 4309, 4329,
    4335, 4344, 4350, 4361, 4367, 4376, 4382, 4407, 4413, 4422, 4428, 4439,
    4445, 4454, 4460, 4480, 4486, 4495, 4501, 4512, 4518, 4527, 4533, 4328,
    4334, 4343, 4349, 4360, 4366, 4375, 4381, 4401, 4407, 4416, 4422, 4433,
    4439, 4448, 4454, 4479, 4485, 4494, 4500, 4511, 4517, 4526, 4532, 4552,
    4558, 4567, 4573, 4584, 4590, 4599, 4605, 4628, 4634, 4643, 4649, 4660,
    4666, 4675, 4681, 4701, 4707, 4716, 4722, 4733, 4739, 4748, 4754, 4779,
    4785, 4794, 4800, 4811, 4817, 4826, 4832, 4852, 4858, 4867, 4873, 4884,
    4890, 4899, 4905, 4769, 4775, 4784, 4790, 4801, 4807, 4816, 4822, 4842,
    4848, 4857, 4863, 4874, 4880, 4889, 4895, 4920, 4926, 4935, 4941, 4952,
    4958, 4967, 4973, 4993, 4999, 5008, 5014, 5025, 5031, 5040, 5046, 5069,
    5075, 5084, 5090, 5101, 5107, 5116, 5122, 5142, 5148, 5157, 5163, 5174,
    5180, 5189, 5195, 5220, 5226, 5235, 5241, 5252, 5258, 5267, 5273, 5293,
    5299, 5308, 5314, 5325, 5331, 5340, 5346, 4604, 4610, 4619, 4625, 4636,
    4642, 4651, 4657, 4677, 4683, 4692, 4698, 4709, 4715, 4724, 4730, 4755,
    4761, 4770, 4776, 4787, 4793, 4802, 4808, 4828, 4834, 4843, 4849, 4860,
    4866, 4875, 4881, 4904, 4910, 4919, 4925, 4936, 4942, 4951, 4957, 4977,
    4983, 4992, 4998, 5009, 5015, 5024, 5030, 5055, 5061, 5070, 5076, 5087,
    5093, 5102, 5108, 5128, 5134, 5143, 5149, 5160, 5166, 5175, 5181, 5045,
    5051, 5060, 5066, 5077, 5083, 5092, 5098, 5118, 5124, 5133, 5139, 5150,
    5156, 5165, 5171, 5196, 5202, 5211, 5217, 5228, 5234, 5243, 5249, 5269,
    5275, 5284, 5290, 5301, 5307, 5316, 5322, 5345, 5351, 5360, 5366, 5377,
    5383, 5392, 5398, 5418, 5424, 5433, 5439, 5450, 5456, 5465, 5471, 5496,
    5502, 5511, 5517, 5528, 5534, 5543, 5549, 5569, 5575, 5584, 5590, 5601,
    5607, 5616, 5622, 5417, 5423, 5432, 5438, 5449, 5455, 5464, 5470, 5490,
    5496, 5505, 5511, 5522, 5528, 5537, 5543, 5568, 5574, 5583, 5589, 5600,
    5606, 5615, 5621, 5641, 5647, 5656, 5662, 5673, 5679, 5688, 5694, 5717,
    5723, 5732, 5738, 5749, 5755, 5764, 5770, 5790, 5796, 5805, 5811, 5822,
    5828, 5837, 5843, 5868, 5874, 5883, 5889, 5900, 5906, 5915, 5921, 5941,
    5947, 5956, 5962, 5973, 5979, 5988, 5994, 5858, 5864, 5873, 5879, 5890,
    5896, 5905, 5911, 5931, 5937, 5946, 5952, 5963, 5969, 5978, 5984, 6009,
    6015, 6024, 6030, 6041, 6047, 6056, 6062, 6082, 6088, 6097, 6103, 6114,
    6120, 6129, 6135, 6158, 6164, 6173, 6179, 6190, 6196, 6205, 6211, 6231,
    6237, 6246, 6252, 6263, 6269, 6278, 6284, 6309, 6315, 6324, 6330, 6341,
    6347, 6356, 6362, 6382, 6388, 6397, 6403, 6414, 6420, 6429, 6435, 3515,
    3521, 3530, 3536, 3547, 3553, 3562, 3568, 3588, 3594, 3603, 3609, 3620,
    3626, 3635, 3641, 3666, 3672, 3681, 3687, 3698, 3704, 3713, 3719, 3739,
    3745, 3754, 3760, 3771, 3777, 3786, 3792, 3815, 3821, 3830, 3836, 3847,
    3853, 3862, 3868, 3888, 3894, 3903, 3909, 3920, 3926, 3935, 3941, 3966,
    3972, 3981, 3987, 3998, 4004, 4013, 4019, 4039, 4045, 4054, 4060, 4071,
    4077, 4086, 4092, 3956, 3962, 3971, 3977, 3988, 3994, 4003, 4009, 4029,
    4035, 4044, 4050, 4061, 4067, 4076, 4082, 4107, 4113, 4122, 4128, 4139,
    4145, 4154, 4160, 4180, 4186, 4195, 4201, 4212, 4218, 4227, 4233, 4256,
    4262, 4271, 4277, 4288, 4294, 4303, 4309, 4329, 4335, 4344, 4350, 4361,
    4367, 4376, 4382, 4407, 4413, 4422, 4428, 4439, 4445, 4454, 4460, 4480,
    4486, 4495, 4501, 4512, 4518, 4527, 4533, 4328, 4334, 4343, 4349, 4360,
    4366, 4375, 4381, 4401, 4407, 4416, 4422, 4433, 4439, 4448, 4454, 4479,
    4485, 4494, 4500, 4511, 4517, 4526, 4532, 4552, 4558, 4567, 4573, 4584,
    4590, 4599, 4605, 4628, 4634, 4643, 4649, 4660, 4666, 4675, 4681, 4701,
    4707, 4716, 4722, 4733, 4739, 4748, 4754, 4779, 4785, 4794, 4800, 4811,
    4817, 4826, 4832, 4852, 4858, 4867, 4873, 4884, 4890, 4899, 4905, 4769,
    4775, 4784, 4790, 4801, 4807, 4816, 4822, 4842, 4848, 4857, 4863, 4874,
    4880, 4889, 4895, 4920, 4926, 4935, 4941, 4952, 4958, 4967, 4973, 4993,
    4999, 5008, 5014, 5025, 5031, 5040, 5046, 5069, 5075, 5084, 5090, 5101,
    5107, 5116, 5122, 5142, 5148, 5157, 5163, 5174, 5180, 5189, 5195, 5220,
    5226, 5235, 5241, 5252, 5258, 5267, 5273, 5293, 5299, 5308, 5314, 5325,
    5331, 5340, 5346, 4604, 4610, 4619, 4625, 4636, 4642, 4651, 4657, 4677,
    4683, 4692, 4698, 4709, 4715, 4724, 4730, 4755, 4761, 4770, 4776, 4787,
    4793, 4802, 4808, 4828, 4834, 4843, 4849, 4860, 4866, 4875, 4881, 4904,
    4910, 4919, 4925, 4936, 4942, 4951, 4957, 4977, 4983, 4992, 4998, 5009,
    5015, 5024, 5030, 5055, 5061, 5070, 5076, 5087, 5093, 5102, 5108, 5128,
    5134, 5143, 5149, 5160, 5166, 5175, 5181, 5045, 5051, 5060, 5066, 5077,
    5083, 5092, 5098, 5118, 5124, 5133, 5139, 5150, 5156, 5165, 5171, 5196,
    5202, 5211, 5217, 5228, 5234, 5243, 5249, 5269, 5275, 5284, 5290, 5301,
    5307, 5316, 5322, 5345, 5351, 5360, 5366, 5377, 5383, 5392, 5398, 5418,
    5424, 5433, 5439, 5450, 5456, 5465, 5471, 5496, 5502, 5511, 5517, 5528,
    5534, 5543, 5549, 5569, 5575, 5584, 5590, 5601, 5607, 5616, 5622, 5417,
    5423, 5432, 5438, 5449, 5455, 5464, 5470, 5490, 5496, 5505, 5511, 5522,
    5528, 5537, 5543, 5568, 5574, 5583, 5589, 5600, 5606, 5615, 5621, 5641,
    5647, 5656, 5662, 5673, 5679, 5688, 5694, 5717, 5723, 5732, 5738, 5749,
    5755, 5764, 5770, 5790, 5796, 5805, 5811, 5822, 5828, 5837, 5843, 5868,
    5874, 5883, 5889, 5900, 5906, 5915, 5921, 5941, 5947, 5956, 5962, 5973,
    5979, 5988, 5994, 5858, 5864, 5873, 5879, 5890, 5896, 5905, 5911, 5931,
    5937, 5946, 5952, 5963, 5969, 5978, 5984, 6009, 6015, 6024, 6030, 6041,
    6047, 6056, 6062, 6082, 6088, 6097, 6103, 6114, 6120, 6129, 6135, 6158,
    6164, 6173, 6179, 6190, 6196, 6205, 6211, 6231, 6237, 6246, 6252, 6263,
    6269, 6278, 6284, 6309, 6315, 6324, 6330, 6341, 6347, 6356, 6362, 6382,
    6388, 6397, 6403, 6414, 6420, 6429, 6435, 5303, 5309, 5318, 5324, 5335,
    5341, 5350, 5356, 5376, 5382, 5391, 5397, 5408, 5414, 5423, 5429, 5454,
    5460, 5469, 5475, 5486, 5492, 5501, 5507, 5527, 5533, 5542, 5548, 5559,
    5565, 5574, 5580, 5603, 5609, 5618, 5624, 5635, 5641, 5650, 5656, 5676,
    5682, 5691, 5697, 5708, 5714, 5723, 5729, 5754, 5760, 5769, 5775, 5786,
    5792, 5801, 5807, 5827, 5833, 5842, 5848, 5859, 5865, 5874, 5880, 5744,
    5750, 5759, 5765, 5776, 5782, 5791, 5797, 5817, 5823, 5832, 5838, 5849,
    5855, 5864, 5870, 5895, 5901, 5910, 5916, 5927, 5933, 5942, 5948, 5968,
    5974, 5983, 5989, 6000, 6006, 6015, 6021, 6044, 6050, 6059, 6065, 6076,
    6082, 6091, 6097, 6117, 6123, 6132, 6138, 6149, 6155, 6164, 6170, 6195,
    6201, 6210, 6216, 6227, 6233, 6242, 6248, 6268, 6274, 6283, 6289, 6300,
    6306, 6315, 6321, 6116, 6122, 6131, 6137, 6148, 6154, 6163, 6169, 6189,
    6195, 6204, 6210, 6221, 6227, 6236, 6242, 6267, 6273, 6282, 6288, 6299,
    6305, 6314, 6320, 6340, 6346, 6355, 6361, 6372, 6378, 6387, 6393, 6416,
    6422, 6431, 6437, 6448, 6454, 6463, 6469, 6489, 6495, 6504, 6510, 6521,
    6527, 6536, 6542, 6567, 6573, 6582, 6588, 6599, 6605, 6614, 6620, 6640,
    6646, 6655, 6661, 6672, 6678, 6687, 6693, 6557, 6563, 6572, 6578, 6589,
    6595, 6604, 6610, 6630, 6636, 6645, 6651, 6662, 6668, 6677, 6683, 6708,
    6714, 6723, 6729, 6740, 6746, 6755, 6761, 6781, 6787, 6796, 6802, 6813,
    6819, 6828, 6834, 6857, 6863, 6872, 6878, 6889, 6895, 6904, 6910, 6930,
    6936, 6945, 6951, 6962, 6968, 6977, 6983, 7008, 7014, 7023, 7029, 7040,
    7046, 7055, 7061, 7081, 7087, 7096, 7102, 7113, 7119, 7128, 7134, 6392,
    6398, 6407, 6413, 6424, 6430, 6439, 6445, 6465, 6471, 6480, 6486, 6497,
    6503, 6512, 6518, 6543, 6549, 6558, 6564, 6575, 6581, 6590, 6596, 6616,
    6622, 6631, 6637, 6648, 6654, 6663, 6669, 6692, 6698, 6707, 6713, 6724,
    6730, 6739, 6745, 6765, 6771, 6780, 6786, 6797, 6803, 6812, 6818, 6843,
    6849, 6858, 6864, 6875, 6881, 6890, 6896, 6916, 6922, 6931, 6937, 6948,
    6954, 6963, 6969, 6833, 6839, 6848, 6854, 6865, 6871, 6880, 6886, 6906,
    6912, 6921, 6927, 6938, 6944, 6953, 6959, 6984, 6990, 6999, 7005, 7016,
    7022, 7031, 7037, 7057, 7063, 7072, 7078, 7089, 7095, 7104, 7110, 7133,
    7139, 7148, 7154, 7165, 7171, 7180, 7186, 7206, 7212, 7221, 7227, 7238,
    7244, 7253, 7259, 7284, 7290, 7299, 7305, 7316, 7322, 7331, 7337, 7357,
    7363, 7372, 7378, 7389, 7395, 7404, 7410, 7205, 7211, 7220, 7226, 7237,
    7243, 7252, 7258, 7278, 7284, 7293, 7299, 7310, 7316, 7325, 7331, 7356,
    7362, 7371, 7377, 7388, 7394, 7403, 7409, 7429, 7435, 7444, 7450, 7461,
    7467, 7476, 7482, 7505, 7511, 7520, 7526, 7537, 7543, 7552, 7558, 7578,
    7584, 7593, 7599, 7610, 7616, 7625, 7631, 7656, 7662, 7671, 7677, 7688,
    7694, 7703, 7709, 7729, 7735, 7744, 7750, 7761};

//------------------------------------------------------------------------------
// Tables for level coding

const uint8_t VP8EncBands[16 + 1] = {
    0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7,
    0  // sentinel
};

//------------------------------------------------------------------------------
// Mode costs

static int GetResidualCost_C(int ctx0, const VP8Residual* const res) {
  int n = res->first;
  // should be prob[VP8EncBands[n]], but it's equivalent for n=0 or 1
  const int p0 = res->prob[n][ctx0][0];
  CostArrayPtr const costs = res->costs;
  const uint16_t* t = costs[n][ctx0];
  // bit_cost(1, p0) is already incorporated in t[] tables, but only if ctx != 0
  // (as required by the syntax). For ctx0 == 0, we need to add it here or it'll
  // be missing during the loop.
  int cost = (ctx0 == 0) ? VP8BitCost(1, p0) : 0;

  if (res->last < 0) {
    return VP8BitCost(0, p0);
  }
  for (; n < res->last; ++n) {
    const int v = abs(res->coeffs[n]);
    const int ctx = (v >= 2) ? 2 : v;
    cost += VP8LevelCost(t, v);
    t = costs[n + 1][ctx];
  }
  // Last coefficient is always non-zero
  {
    const int v = abs(res->coeffs[n]);
    assert(v != 0);
    cost += VP8LevelCost(t, v);
    if (n < 15) {
      const int b = VP8EncBands[n + 1];
      const int ctx = (v == 1) ? 1 : 2;
      const int last_p0 = res->prob[b][ctx][0];
      cost += VP8BitCost(0, last_p0);
    }
  }
  return cost;
}

static void SetResidualCoeffs_C(const int16_t* WEBP_RESTRICT const coeffs,
                                VP8Residual* WEBP_RESTRICT const res) {
  int n;
  res->last = -1;
  assert(res->first == 0 || coeffs[0] == 0);
  for (n = 15; n >= 0; --n) {
    if (coeffs[n]) {
      res->last = n;
      break;
    }
  }
  res->coeffs = coeffs;
}

//------------------------------------------------------------------------------
// init function

VP8GetResidualCostFunc VP8GetResidualCost;
VP8SetResidualCoeffsFunc VP8SetResidualCoeffs;

extern VP8CPUInfo VP8GetCPUInfo;
extern void VP8EncDspCostInitMIPS32(void);
extern void VP8EncDspCostInitMIPSdspR2(void);
extern void VP8EncDspCostInitSSE2(void);
extern void VP8EncDspCostInitNEON(void);

WEBP_DSP_INIT_FUNC(VP8EncDspCostInit) {
  VP8GetResidualCost = GetResidualCost_C;
  VP8SetResidualCoeffs = SetResidualCoeffs_C;

  // If defined, use CPUInfo() to overwrite some pointers with faster versions.
  if (VP8GetCPUInfo != NULL) {
#if defined(WEBP_USE_MIPS32)
    if (VP8GetCPUInfo(kMIPS32)) {
      VP8EncDspCostInitMIPS32();
    }
#endif
#if defined(WEBP_USE_MIPS_DSP_R2)
    if (VP8GetCPUInfo(kMIPSdspR2)) {
      VP8EncDspCostInitMIPSdspR2();
    }
#endif
#if defined(WEBP_HAVE_SSE2)
    if (VP8GetCPUInfo(kSSE2)) {
      VP8EncDspCostInitSSE2();
    }
#endif
#if defined(WEBP_HAVE_NEON)
    if (VP8GetCPUInfo(kNEON)) {
      VP8EncDspCostInitNEON();
    }
#endif
  }
}

//------------------------------------------------------------------------------
